Volume 497 Issue 7450, 23 May 2013

Chiral molecules exist as enantiomers that form non-superimposable mirror images, and chirality has a fundamental role in many aspects of chemistry and biology. It is notoriously difficult to detect and quantify chirality because conventional spectroscopic methods exploit weak effects. Patterson et al. now show that microwave spectroscopy combined with a switched electric field can map the sign of an electric dipole Rabi frequency � a variable that depends directly on the chirality of the molecule � onto the phase of emitted microwave radiation. The effect is then used to determine the chirality of cold gas-phase molecules, illustrated with S- and R enantiomers of 1,2-propanediol and their racemic mixture. The method produces large and definitive signatures of chirality, and is both sensitive and species-selective � making it a potentially ideal and unique tool for determining the chirality of multiple species in a mixture. The red and blue traces depicted in the image come from digitized signals from S and R 1,2-propanediol. Cover design: pikovsky.org

This Week

News In Focus


  • News |

    Space telescope’s mission to find planets outside the Solar System is probably over.

    • Ron Cowen
  • Features

  • News Feature |

    Ed Stone has spent 36 years guiding the twin Voyager spacecraft through the Solar System. Next stop, interstellar space.

    • Alexandra Witze
  • News Feature |

    More and more studies show that being overweight does not always shorten life — but some public-health researchers would rather not talk about them.

    • Virginia Hughes





  • Outlook |

    • Tony Scully
  • Outlook |

    One of sleep's most important functions is processing memory. Researchers are now starting to figure out how the brain helps us learn when we're asleep.

    • Kerri Smith
  • Outlook |

    Studies that restrict sleep show why a lack of shut-eye can lead to serious chronic disease.

    • Elie Dolgin
  • Outlook |

    A growing body of evidence shows that getting a good night's sleep plays an important role in regulating the body's metabolism.

    • Brian Owens
  • Outlook |

    The causal relationships between lack of sleep and mood disorders remain murky. But one thing is clear as day: better sleep can have psychological benefits.

    • Sarah DeWeerdt
  • Outlook |

    A combination of drugs and cognitive behavioural therapy may finally put an end to the misery of sleepless nights.

    • James Mitchell Crow
  • Outlook |

    Sleep disturbances may be an early sign of neurodegenerative diseases — but could sleep deficits cause these conditions in the first place?

    • Moheb Costandi


    News & Views

  • News & Views |

    Natural variations in the rate of protein translation in cellular organelles called mitochondria have been found to correlate with lifespan, suggesting a unified mechanism for the effects of metabolic alterations on longevity. See Article p.451

    • Suzanne Wolff
    •  & Andrew Dillin
  • News & Views |

    Dengue virus has a highly ordered structure when grown in mosquito cells at 28 °C. The finding that the virus expands into a less ordered form at 37 °C indicates that the human immune system does not see it as we previously thought.

    • Felix A. Rey
  • News & Views |

    How the enzyme diacylglycerol kinase can form membrane anchors and an active site from so few amino-acid residues has long been a mystery. Crystal structures reveal that it gets by with a little help from its friends. See Letter p.521

    • Jimin Zheng
    •  & Zongchao Jia
  • News & Views |

    Traditional methods for detecting and identifying the handedness of molecules — their chirality — have been based on the same theoretical concept. A technique has been reported that departs from this paradigm. See Letter p.475

    • Laurence A. Nafie
  • News & Views |

    Aerogels have many potential applications but usually suffer from poor elasticity. The synergistic assembly of carbon nanotubes and graphene has now allowed multifunctional, ultra-lightweight and super-elastic aerogels to be made.

    • Wencai Ren
    •  & Hui-Ming Cheng
  • News & Views |

    Unusual DNA structures, such as G-quadruplexes, can stall DNA replication with drastic consequences for the cell. The Pif1 helicase family of enzymes has evolved to disentangle these structures efficiently. See Article p.458

    • Sergei M. Mirkin
  • Articles

  • Article |

    Mitochondrial ribosomal proteins have been identified as longevity regulators in C. elegans and mammalian systems, their role in longevity is linked to mitonuclear protein imbalance and the mitochondrial unfolded protein response.

    • Riekelt H. Houtkooper
    • , Laurent Mouchiroud
    • , Dongryeol Ryu
    • , Norman Moullan
    • , Elena Katsyuba
    • , Graham Knott
    • , Robert W. Williams
    •  & Johan Auwerx
  • Article |

    In vitro and in vivo, the yeast Pif1 helicase is able to unwind four-stranded G-quadruplex (G4) DNA efficiently and suppress the genomic instability that occurs at such structures; these G4 maintenance activities are conserved among evolutionarily diverse Pif1 family helicases, including human PIF1, demonstrating the importance of this activity throughout evolution.

    • Katrin Paeschke
    • , Matthew L. Bochman
    • , P. Daniela Garcia
    • , Petr Cejka
    • , Katherine L. Friedman
    • , Stephen C. Kowalczykowski
    •  & Virginia A. Zakian
  • Letters

  • Letter |

    A magnetohydrodynamic simulation of a magnetized plasma at high conductivity shows that, whereas the magnetic flux can be considered ‘frozen’ into the medium for laminar flow, in a turbulent medium the motion of the field lines can become indeterministic, leading to a breakdown in flux freezing.

    • Gregory Eyink
    • , Ethan Vishniac
    • , Cristian Lalescu
    • , Hussein Aluie
    • , Kalin Kanov
    • , Kai Bürger
    • , Randal Burns
    • , Charles Meneveau
    •  & Alexander Szalay
  • Letter |

    A metamaterial is fabricated that yields a ‘left-handed’ response — characterized by a negative refractive index — to ultraviolet light incident at all angles, allowing both passive and active flat lensing of arbitrarily shaped, two-dimensional objects beyond the near field in free space.

    • Ting Xu
    • , Amit Agrawal
    • , Maxim Abashin
    • , Kenneth J. Chau
    •  & Henri J. Lezec
  • Letter |

    Microwave spectroscopy is used to map the sign of an electric dipole Rabi frequency — which depends directly on the chirality of the molecule — onto the phase of emitted microwave radiation, thereby determining the chirality of cold gas-phase molecules.

    • David Patterson
    • , Melanie Schnell
    •  & John M. Doyle
  • Letter |

    In the quasibiennial oscillation, the prevailing wind direction in the tropical stratosphere switches between easterly and westerly and back with a period of about two years; now an analysis of a suite of radiosonde wind data reveals that the amplitude of this oscillation has weakened over the past six decades, most probably as a result of increased tropical upwelling in the lower stratosphere.

    • Yoshio Kawatani
    •  & Kevin Hamilton
  • Letter |

    In an auditory frequency discrimination task in rats, channelrhodopsin-2-mediated stimulation of corticostriatal neurons biases decisions in the direction predicted by the frequency tuning of the stimulated neurons, whereas archaerhodopsin-3-mediated inactivation biases decisions in the opposite direction.

    • Petr Znamenskiy
    •  & Anthony M. Zador
  • Letter |

    Deletion of a single gene, Taar4, in mice abolishes aversion to low concentrations of volatile amines and to the odour of predator urine, indicating that individual olfactory receptor genes can affect odour perception.

    • Adam Dewan
    • , Rodrigo Pacifico
    • , Ross Zhan
    • , Dmitry Rinberg
    •  & Thomas Bozza
  • Letter |

    Sema3A, a member of the semaphorin family of proteins, is shown to regulate bone remodelling indirectly by modulating sensory nerve development in mice.

    • Toru Fukuda
    • , Shu Takeda
    • , Ren Xu
    • , Hiroki Ochi
    • , Satoko Sunamura
    • , Tsuyoshi Sato
    • , Shinsuke Shibata
    • , Yutaka Yoshida
    • , Zirong Gu
    • , Ayako Kimura
    • , Chengshan Ma
    • , Cheng Xu
    • , Waka Bando
    • , Koji Fujita
    • , Kenichi Shinomiya
    • , Takashi Hirai
    • , Yoshinori Asou
    • , Mitsuhiro Enomoto
    • , Hideyuki Okano
    • , Atsushi Okawa
    •  & Hiroshi Itoh
  • Letter |

    Herpes simplex virus 2-infected individuals are shown to have skin-tissue-resident CD8αα+ T cells that persist at the portal of virus release in genital skin and mucosa, possess oligoclonal T-cell-receptor-β CDR3 sequences that are stable over time, and express gene signatures of antiviral and cytolytic function indicative of viral-specific immune surveillance.

    • Jia Zhu
    • , Tao Peng
    • , Christine Johnston
    • , Khamsone Phasouk
    • , Angela S. Kask
    • , Alexis Klock
    • , Lei Jin
    • , Kurt Diem
    • , David M. Koelle
    • , Anna Wald
    • , Harlan Robins
    •  & Lawrence Corey
  • Letter |

    TLR4 stimulation is known to contribute to acute lung injury after administration of inactivated influenza virus; here, the synthetic TLR4 antagonist Eritoran is shown to protect mice from death after infection with a lethal dose of the virus.

    • Kari Ann Shirey
    • , Wendy Lai
    • , Alison J. Scott
    • , Michael Lipsky
    • , Pragnesh Mistry
    • , Lioubov M. Pletneva
    • , Christopher L. Karp
    • , Jaclyn McAlees
    • , Theresa L. Gioannini
    • , Jerrold Weiss
    • , Wilbur H. Chen
    • , Robert K. Ernst
    • , Daniel P. Rossignol
    • , Fabian Gusovsky
    • , Jorge C. G. Blanco
    •  & Stefanie N. Vogel
  • Letter |

    Lamin and emerin mutations causing cardiomyopathies are associated with an impairment in actin dynamics, resulting in aberrant nuclear translocation and downstream signalling of the transcription factor MKL1, which is pivotal for cardiac development.

    • Chin Yee Ho
    • , Diana E. Jaalouk
    • , Maria K. Vartiainen
    •  & Jan Lammerding
  • Letter |

    The proteasome degrades ubiquitin-conjugated substrates; here, structural and functional insights from studies in yeast reveal that it is reconfigured during chaperone-mediated assembly.

    • Soyeon Park
    • , Xueming Li
    • , Ho Min Kim
    • , Chingakham Ranjit Singh
    • , Geng Tian
    • , Martin A. Hoyt
    • , Scott Lovell
    • , Kevin P. Battaile
    • , Michal Zolkiewski
    • , Philip Coffino
    • , Jeroen Roelofs
    • , Yifan Cheng
    •  & Daniel Finley
  • Letter |

    Analysis of whole-genome sequence data of Icelandic individuals has revealed a rare nonsense mutation within the LGR4 gene that is strongly associated with, among other things, low bone mineral density, late onset of menarche, and increased risk of biliary tract cancer.

    • Unnur Styrkarsdottir
    • , Gudmar Thorleifsson
    • , Patrick Sulem
    • , Daniel F. Gudbjartsson
    • , Asgeir Sigurdsson
    • , Aslaug Jonasdottir
    • , Adalbjorg Jonasdottir
    • , Asmundur Oddsson
    • , Agnar Helgason
    • , Olafur T. Magnusson
    • , G. Bragi Walters
    • , Michael L. Frigge
    • , Hafdis T. Helgadottir
    • , Hrefna Johannsdottir
    • , Kristin Bergsteinsdottir
    • , Margret H. Ogmundsdottir
    • , Jacqueline R. Center
    • , Tuan V. Nguyen
    • , John A. Eisman
    • , Claus Christiansen
    • , Erikur Steingrimsson
    • , Jon G. Jonasson
    • , Laufey Tryggvadottir
    • , Gudmundur I. Eyjolfsson
    • , Asgeir Theodors
    • , Thorvaldur Jonsson
    • , Thorvaldur Ingvarsson
    • , Isleifur Olafsson
    • , Thorunn Rafnar
    • , Augustine Kong
    • , Gunnar Sigurdsson
    • , Gisli Masson
    • , Unnur Thorsteinsdottir
    •  & Kari Stefansson
  • Letter |

    This study presents the crystal structures of three functional forms of diacylglycerol kinase, an integral membrane protein that catalyses a crucial step in oligosaccharide and lipopolysaccharide synthesis and assembly; these X-ray structures are markedly different from the only other structure available for this unique kinase that was solved using solution NMR.

    • Dianfan Li
    • , Joseph A. Lyons
    • , Valerie E. Pye
    • , Lutz Vogeley
    • , David Aragão
    • , Colin P. Kenyon
    • , Syed T. A. Shah
    • , Christine Doherty
    • , Margaret Aherne
    •  & Martin Caffrey


Nature Outlook

  • Nature Outlook |


    Researchers are defining the various functions of sleep, from how we learn to the regulation of metabolism and immunity. Insufficient sleep, a growing problem in modern society, can knock our biological clocks out of kilter, sometimes leading to chronic disease and neurodegeneration. New ways to treat troubled sleeping are being developed, and better sleep practice can help people with mood disorders.

Newsletter Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing